Effective environmental management depends on a detailed knowledge of the distribution of species. But taxonomists are in short supply, and some species can be difficult to identify, even for experts. Eawag, in collaboration ...

One hundred years after the outbreak of the First World War, the flower that has come to symbolise the lives lost in conflict – the poppy – is disappearing from former battle fields of northern France and Belgian Flanders. ...

In the battle between native and invasive wetland plants, a new Duke University study finds climate change may tip the scales in favor of the invaders—but it's going to be more a war of attrition than a frontal assault.

Scientists monitoring incoming tsunami debris were taken aback last spring when some 30 fishing vessels from Japan washed ashore along the Pacific Northwest coast – many of them covered in living organisms indigenous to ...

Invasive species

Invasive species is a phrase with several definitions. The first definition expresses the phrase in terms of non-indigenous species (e.g. plants or animals) that adversely affect the habitats they invade economically, environmentally or ecologically. It has been used in this sense by government organizations as well as conservation groups such as the IUCN (International Union for Conservation of Nature).

The second definition broadens the boundaries to include both native and non-native species that heavily colonize a particular habitat.

The third definition is an expansion of the first and defines an invasive species as a widespread non-indigenous species. This last definition is arguably too broad as not all non-indigenous species necessarily have an adverse effect on their adopted environment. An example of this broader use would include the claim that the common goldfish (Carassius auratus) is invasive. Although it is common outside its range globally, it almost never appears in harmful densities.

Because of the ambiguity of its definition, the phrase invasive species is often criticized as an imprecise term within the field of ecology. This article concerns the first two definitions; for the third, see introduced species.